.box{
  width: 500px;
  height: 400px;
  margin: 50px auto;
  border:solid 1px #025;
  text-align: center;
  line-height: 400px;
  font-size: 24px;
  user-select: none;
}

.slider{
  width: 640px;
  height: 360px;
  margin: 100px auto;
  position: relative;
  overflow: hidden;
}

.slider .img-wrapper{
  width: 500%;
  position: absolute;
  left: 0;
  transition: all 0.5s;
}

.slider img{
  width: 20%;
  display:block;
  float: left;
}

.slider:hover .btn{
  filter: opacity(0.8)
}

.btn{
  width: 60px;
  height: 60px;
  background: white;
  position: absolute;
  top: 150px;
  border-radius: 50%;
  text-align: center;
  line-height: 60px;
  font-size: 20px;
  filter: opacity(0);
  user-select: none;
  cursor: pointer;
  transition: all 0.5s;
}

.prev{
  left: 0;
}

.next{
  right: 0;
}

#root{
  height: 100vh;
  background: radial-gradient(#aef, #236);
  overflow: hidden;
}

*{
  margin:0;
  padding: 0;
}